"...the bill requires the interoperability of PTC communications systems, so that a locomotive on any railroad can operate on any other railroad's track using the same control systems..."

Interoperability of such systems shall be mandated as there are systems from different manufacturers put together into the service, those shall be compatible to each other in order to safeguard lives. I do not understand why such key requirement is not mandated by the legislation.

Keep up the good work. This seems important as we get more high-speed rail systems or maybe even self-driving cars that my hook together in rail systems for long distance travel? WIth high speed rail coming into California soon, it will help to have these details worked out. (Though I assume high speed rail will be on its own separate track.)